Fevold Brick M, Meyer Michael W, Rasmussen Paul W, Temple Stanley A
Department of Wildlife Ecology, 226 Russell Labs, University of Wisconsin-Madison, Madison, WI 53706, USA.
Ecotoxicology. 2003 Feb-Aug;12(1-4):83-93. doi: 10.1023/a:1022545130918.
A long term field study was initiated by the Wisconsin Department of Natural Resources in 1992 to elucidate patterns of common loon (Gavia immer) mercury (Hg) exposure. Analysis of loon blood and feather samples collected from recaptured adult loons in Wisconsin 1992-2000 found evidence of a decline in overall body burdens of mercury in common loons for this region. The interval between sampling individual loons spanned 2-8 years, a sufficient length of time to observe a change in tissue Hg concentrations. Loon chick blood Hg levels declined by 4.9% annually for chicks sampled on 33 lakes during the period 1992-2000. This is the first evidence we are aware of showing a recent regional annual decrease in common loon Hg exposure. Repeated captures of wild loon chicks in Wisconsin shows that blood Hg concentrations can increase during the period of rapid feather growth (weeks 2-5), although the rate of increase is very slow. Mean egg Hg levels ranged from 0.19 to 0.87 microg Hg/g wet weight (ww) in samples collected 1996-2000. Egg Hg concentration was inversely and significantly related to lake pH (p < 0.0001; r2 = 0.55). Adults and chicks were often captured simultaneous during the period 1992-2000. Correlations were highest between sibling blood Hg levels (r = 0.88) and chick blood and adult blood (male r = 0.61, female r = 0.52) Hg levels, likely reflecting the influence of the Hg content of prey from the natal lake on loon blood Hg levels. The relationship between feathers and blood of adults and that of chick blood and adult feathers was weaker.
1992年，威斯康星州自然资源部发起了一项长期实地研究，以阐明普通潜鸟（矛斑潜鸟）汞（Hg）暴露模式。对1992 - 2000年在威斯康星州重新捕获的成年潜鸟采集的血液和羽毛样本进行分析后发现，该地区普通潜鸟体内汞的总体负担有所下降。对个体潜鸟的采样间隔为2 - 8年，这一时间跨度足以观察到组织汞浓度的变化。1992 - 2000年期间，在33个湖泊采集的潜鸟雏鸟血液汞水平每年下降4.9%。这是我们所知的首个表明普通潜鸟汞暴露近期出现区域性年度下降的证据。在威斯康星州对野生潜鸟雏鸟的多次捕获显示，在快速换羽期（第2 - 5周），血液汞浓度会升高，尽管升高速度非常缓慢。1996 - 2000年采集的样本中，平均蛋汞水平为0.19至0.87微克汞/克湿重（ww）。蛋汞浓度与湖泊pH值呈显著负相关（p < 0.0001；r2 = 0.55）。1992 - 2000年期间，经常同时捕获成年潜鸟和雏鸟。同胞血液汞水平之间的相关性最高（r = 0.88），雏鸟血液与成年血液（雄性r = 0.61，雌性r = 0.52）汞水平之间的相关性也较高，这可能反映了出生地湖泊猎物的汞含量对潜鸟血液汞水平的影响。成年潜鸟羽毛与血液之间以及雏鸟血液与成年潜鸟羽毛之间的关系较弱。
